Wl. Lorimer et al., CORRELATION OF EXPERIMENTAL-DATA AND 3-DIMENSIONAL FINITE-ELEMENT MODELING OF A SPINNING MAGNET ARRAY, IEEE transactions on magnetics, 30(5), 1994, pp. 3004-3007
A magnet array was spun above an aluminum disk, and the drag torque wa
s measured for various speeds and pp sizes. Drag torques calculated us
ing a three-dimensional finite element program were consistent with me
asured values. The finite element model was also used to determine the
effects of the polarity and position of magnets in the source array.
The peak torque was shown to occur when magnets are located at a radiu
s equal to 70% of the disk radius. A magnet array with alternate magne
ts reversed was shown to produce more than twice the drag of an array
comprised of parallel magnets. An approximation for fields under the m
agnet centers was obtained using a two-dimensional analytical solution
.